This tuna salad is simple to make - it comes together in under 30 minutes - but is so flavourful and beautiful that it feels like something you'd get from a high-end cafe. Use the freshest, highest-quality tuna that you can find and note that the dressing can be made several days in advance.
First, make the dressing, In a jar or airtight container, add all of the ingredients along with a few grinds of black pepper. Ensure the lid is sealed securely and shake vigorously until the dressing is emulsified and the miso paste is fully incorporated. Set aside, ensure to shake again before dressing the salad.
Next, season both sides of the tuna liberally with salt and pepper. Sprinkle over 2 tbsp of sesame seeds, ensuring each side is completely coated - press the seeds into the fish to adhere them to the flesh. Set aside.
Add 1 tbsp of neutral oil to a large skillet and set it over medium-high heat. Once the oil is simmering, add the tuna to the pan. Cook for 90 seconds on each side. Remove the tuna from the pan and allow to rest for at least 5 minutes before slicing into thin strips with a sharp chef's knife.
While the tuna is resting, add the lettuce, scallions, edamame, cucumber, chili, cilantro, peanuts and the remaining teaspoon of sesame seeds to a large salad bowl. Pour over the dressing and plenty of freshly ground pepper and toss to combine, Portion the salad into individual dishes.
Arrange the tuna slices equally over the portioned salad. Serve immediately.